Humans ; Epilepsy, Temporal Lobe/surgery* ; Mossy Fibers, Hippocampal ; Brain-Derived Neurotrophic Factor ; Dentate Gyrus

Drug-refractory epilepsy (DRE) may be treated by surgical intervention. Intracranial EEG has been widely used to localize the epileptogenic zone (EZ). Most studies of epileptic network focus on the features of EZ nodes, such as centrality and degrees. It is difficult to apply those features to the treatment of individual patients. In this study, we proposed a spatial neighbor expansion approach for EZ localization based on a neural computational model and epileptic network reconstruction. The virtual resection method was also used to validate the effectiveness of our approach. The electrocorticography (ECoG) data from 11 patients with DRE were analyzed in this study. Both interictal data and surgical resection regions were used. The results showed that the rate of consistency between the localized regions and the surgical resections in patients with good outcomes was higher than that in patients with poor outcomes. The average deviation distance of the localized region for patients with good outcomes and poor outcomes were 15 mm and 36 mm, respectively. Outcome prediction showed that the patients with poor outcomes could be improved when the brain regions localized by the proposed approach were treated. This study provides a quantitative analysis tool for patient-specific measures for potential surgical treatment of epilepsy.
Humans ; Epilepsy/surgery* ; Brain/surgery* ; Electrocorticography/methods* ; Drug Resistant Epilepsy/surgery* ; Brain Mapping/methods* ; Electroencephalography/methods*

Focal cortical dysplasia (FCD) is one of the most common causes of drug-resistant epilepsy. Dysmorphic neurons are the major histopathological feature of type II FCD, but their role in seizure genesis in FCD is unclear. Here we performed whole-cell patch-clamp recording and morphological reconstruction of cortical principal neurons in postsurgical brain tissue from drug-resistant epilepsy patients. Quantitative analyses revealed distinct morphological and electrophysiological characteristics of the upper layer dysmorphic neurons in type II FCD, including an enlarged soma, aberrant dendritic arbors, increased current injection for rheobase action potential firing, and reduced action potential firing frequency. Intriguingly, the upper layer dysmorphic neurons received decreased glutamatergic and increased GABAergic synaptic inputs that were coupled with upregulation of the Na⁺-K⁺-Cl^- cotransporter. In addition, we found a depolarizing shift of the GABA reversal potential in the CamKII-cre::PTEN^flox/flox mouse model of drug-resistant epilepsy, suggesting that enhanced GABAergic inputs might depolarize dysmorphic neurons. Thus, imbalance of synaptic excitation and inhibition of dysmorphic neurons may contribute to seizure genesis in type II FCD.
Animals ; Drug Resistant Epilepsy/surgery* ; Epilepsy/pathology* ; Malformations of Cortical Development/pathology* ; Malformations of Cortical Development, Group I ; Mice ; Neurons/pathology* ; Seizures/pathology*

Temporal lobe epilepsy, with a variety of etiological, symptomatic, electrophysiological characteristics, has the highest incidence among all focal epilepsy, and a high rate of progression to refractory epilepsy. Surgery is an effective treatment, but traditional methods are usually difficult to accurately locate the epileptogenic zone, which may be resolved by stereotactic-electroencephalogram(SEEG) technique. Radiofrequency thermocoagulation and MRI-guided laser interstitial thermal therapy based on SEEG provide a new accurate and minimally invasive choice for refractory epilepsy patients with high surgical risk and difficulty.
Drug Resistant Epilepsy/surgery* ; Electrocoagulation/methods* ; Electroencephalography ; Epilepsy, Temporal Lobe/surgery* ; Humans ; Stereotaxic Techniques

Brain ; Epilepsy/surgery* ; Humans

BACKGROUND: Patients with temporal lobe epilepsy (TLE) originating from different seizure onset zones had distinct electrophysiological characteristics and surgical outcomes. In this study, we aimed to investigate the relationship between the origin and prognosis of TLE, and the stereoelectroencephalography (SEEG) features. METHODS: Thirty patients with TLE, who underwent surgical treatment in our functional neurosurgery department from January 2016 to December 2017, were enrolled in this study. All patients underwent anterior temporal lobectomy after an invasive pre-operative evaluation with SEEG. Depending on the epileptic focus location, patients were divided into those with medial temporal lobe seizures (MTLS) and those with lateral temporal lobe seizures (LTLS). The Engel classification was used to evaluate operation effectiveness, and the Kaplan-Meier analysis was used to detect seizure-free duration. RESULTS: The mean follow-up time was 25.7 ± 4.8 months. Effectiveness was 63.3% for Engel I (n = 19), 13.3% for Engel II, 3.3% for Engel III, and 20.0% for Engel IV. According to the SEEG, 60.0% (n = 18) had MTLS, and 40.0% (n = 12) had LTLS. Compared with the MTLS group, the operation age of those with LTLS was significantly greater (26.9 ± 6.9 vs. 29.9 ± 12.5 years, t = -0.840, P = 0.009) with longer epilepsy duration (11.9 ± 6.0 vs. 17.9 ± 12.1 years, t = -1.801, P = 0.038). Patients with MTLS had a longer time interval between ictal onset to seizure (67.3 ± 59.1 s vs. 29.3 ± 24.4 s, t = 2.017, P = 0.008). The most common SEEG ictal pattern was a sharp/spike-wave rhythm in the MTLS group (55.6%) and low-voltage fast activity in the LTLS group (58.3%). Compared with the LTLS group, patients with MTLS had a more favorable prognosis (41.7% vs. 77.8%, P = 0.049). Post-operative recurrence was more likely to occur within three months after the operation for both groups, and there appeared to be a stable long-term outcome. CONCLUSION Patients with MTLS, who accounted for three-fifths of patients with TLE, showed a more favorable surgical outcome.
Anterior Temporal Lobectomy ; Electroencephalography ; Epilepsy, Temporal Lobe/surgery* ; Humans ; Stereotaxic Techniques ; Treatment Outcome

Consensus ; Epilepsy ; complications ; Humans ; Tuberous Sclerosis ; complications ; surgery

Blood Loss, Surgical ; prevention & control ; Epilepsy ; chemically induced ; Humans ; Orthopedic Procedures ; Spine ; surgery ; Tranexamic Acid ; adverse effects

Epilepsy ; diagnostic imaging ; surgery ; Humans ; Magnetic Resonance Imaging ; Postoperative Complications ; etiology ; Preoperative Care

OBJECTIVETo investigate the clinical features and surgical strategy for pediatric intractable epilepsy due to posterior quadrantic cortical dysplasia and to assess the surgical outcomes.

METHODSThe clinical features and preoperative evaluation results of 14 children with intractable epilepsy due to posterior quadrantic cortical dysplasia were retrospectively analyzed. The localization values of video-electroencephalography and intraoperative monitoring and the indications, advantages and disadvantages of temporoparietooccipital disconnection were evaluated.

RESULTSThe 14 children had different seizure types, of which spasm was the most common one. The lesions of cortical dysplasia involved the central cerebral region in 2 cases. After temporoparietooccipital disconnection in 14 patients, 13 cases were seizure-free; only one case still had seizures, but the frequency dropped by more than 50%.

CONCLUSIONSTemporoparietooccipital disconnection is a safe and effective surgical procedure for children with intractable epilepsy due to posterior quadrantic cortical dysplasia.

Child ; Child, Preschool ; Electroencephalography ; Epilepsy ; etiology ; physiopathology ; surgery ; Evoked Potentials, Somatosensory ; Female ; Humans ; Infant ; Male ; Malformations of Cortical Development ; complications